Adding admin controller and service

Program.cs

@@ -54,6 +54,7 @@ builder.Services.AddSingleton<ItemService>();
 builder.Services.AddSingleton<BlacklistService>();
 builder.Services.AddSingleton<AuctionService>();
 builder.Services.AddSingleton<ChatService>();
+builder.Services.AddSingleton<AdminService>();
 
 var jwtKey = builder.Configuration["Jwt:Key"];
 var keyBytes = Encoding.UTF8.GetBytes(jwtKey);
@@ -108,4 +109,4 @@ app.UseAuthorization();
 
 app.MapControllers();
 
-app.Run();
+app.Run();